v4.19.13 snapshot.
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
new file mode 100644
index 0000000..a2b3d9d
--- /dev/null
+++ b/kernel/irq/chip.c
@@ -0,0 +1,1450 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
+ * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
+ *
+ * This file contains the core interrupt handling code, for irq-chip based
+ * architectures. Detailed information is available in
+ * Documentation/core-api/genericirq.rst
+ */
+
+#include <linux/irq.h>
+#include <linux/msi.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/kernel_stat.h>
+#include <linux/irqdomain.h>
+
+#include <trace/events/irq.h>
+
+#include "internals.h"
+
+static irqreturn_t bad_chained_irq(int irq, void *dev_id)
+{
+ WARN_ONCE(1, "Chained irq %d should not call an action\n", irq);
+ return IRQ_NONE;
+}
+
+/*
+ * Chained handlers should never call action on their IRQ. This default
+ * action will emit warning if such thing happens.
+ */
+struct irqaction chained_action = {
+ .handler = bad_chained_irq,
+};
+
+/**
+ * irq_set_chip - set the irq chip for an irq
+ * @irq: irq number
+ * @chip: pointer to irq chip description structure
+ */
+int irq_set_chip(unsigned int irq, struct irq_chip *chip)
+{
+ unsigned long flags;
+ struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
+
+ if (!desc)
+ return -EINVAL;
+
+ if (!chip)
+ chip = &no_irq_chip;
+
+ desc->irq_data.chip = chip;
+ irq_put_desc_unlock(desc, flags);
+ /*
+ * For !CONFIG_SPARSE_IRQ make the irq show up in
+ * allocated_irqs.
+ */
+ irq_mark_irq(irq);
+ return 0;
+}
+EXPORT_SYMBOL(irq_set_chip);
+
+/**
+ * irq_set_type - set the irq trigger type for an irq
+ * @irq: irq number
+ * @type: IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h
+ */
+int irq_set_irq_type(unsigned int irq, unsigned int type)
+{
+ unsigned long flags;
+ struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
+ int ret = 0;
+
+ if (!desc)
+ return -EINVAL;
+
+ ret = __irq_set_trigger(desc, type);
+ irq_put_desc_busunlock(desc, flags);
+ return ret;
+}
+EXPORT_SYMBOL(irq_set_irq_type);
+
+/**
+ * irq_set_handler_data - set irq handler data for an irq
+ * @irq: Interrupt number
+ * @data: Pointer to interrupt specific data
+ *
+ * Set the hardware irq controller data for an irq
+ */
+int irq_set_handler_data(unsigned int irq, void *data)
+{
+ unsigned long flags;
+ struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
+
+ if (!desc)
+ return -EINVAL;
+ desc->irq_common_data.handler_data = data;
+ irq_put_desc_unlock(desc, flags);
+ return 0;
+}
+EXPORT_SYMBOL(irq_set_handler_data);
+
+/**
+ * irq_set_msi_desc_off - set MSI descriptor data for an irq at offset
+ * @irq_base: Interrupt number base
+ * @irq_offset: Interrupt number offset
+ * @entry: Pointer to MSI descriptor data
+ *
+ * Set the MSI descriptor entry for an irq at offset
+ */
+int irq_set_msi_desc_off(unsigned int irq_base, unsigned int irq_offset,
+ struct msi_desc *entry)
+{
+ unsigned long flags;
+ struct irq_desc *desc = irq_get_desc_lock(irq_base + irq_offset, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
+
+ if (!desc)
+ return -EINVAL;
+ desc->irq_common_data.msi_desc = entry;
+ if (entry && !irq_offset)
+ entry->irq = irq_base;
+ irq_put_desc_unlock(desc, flags);
+ return 0;
+}
+
+/**
+ * irq_set_msi_desc - set MSI descriptor data for an irq
+ * @irq: Interrupt number
+ * @entry: Pointer to MSI descriptor data
+ *
+ * Set the MSI descriptor entry for an irq
+ */
+int irq_set_msi_desc(unsigned int irq, struct msi_desc *entry)
+{
+ return irq_set_msi_desc_off(irq, 0, entry);
+}
+
+/**
+ * irq_set_chip_data - set irq chip data for an irq
+ * @irq: Interrupt number
+ * @data: Pointer to chip specific data
+ *
+ * Set the hardware irq chip data for an irq
+ */
+int irq_set_chip_data(unsigned int irq, void *data)
+{
+ unsigned long flags;
+ struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
+
+ if (!desc)
+ return -EINVAL;
+ desc->irq_data.chip_data = data;
+ irq_put_desc_unlock(desc, flags);
+ return 0;
+}
+EXPORT_SYMBOL(irq_set_chip_data);
+
+struct irq_data *irq_get_irq_data(unsigned int irq)
+{
+ struct irq_desc *desc = irq_to_desc(irq);
+
+ return desc ? &desc->irq_data : NULL;
+}
+EXPORT_SYMBOL_GPL(irq_get_irq_data);
+
+static void irq_state_clr_disabled(struct irq_desc *desc)
+{
+ irqd_clear(&desc->irq_data, IRQD_IRQ_DISABLED);
+}
+
+static void irq_state_clr_masked(struct irq_desc *desc)
+{
+ irqd_clear(&desc->irq_data, IRQD_IRQ_MASKED);
+}
+
+static void irq_state_clr_started(struct irq_desc *desc)
+{
+ irqd_clear(&desc->irq_data, IRQD_IRQ_STARTED);
+}
+
+static void irq_state_set_started(struct irq_desc *desc)
+{
+ irqd_set(&desc->irq_data, IRQD_IRQ_STARTED);
+}
+
+enum {
+ IRQ_STARTUP_NORMAL,
+ IRQ_STARTUP_MANAGED,
+ IRQ_STARTUP_ABORT,
+};
+
+#ifdef CONFIG_SMP
+static int
+__irq_startup_managed(struct irq_desc *desc, struct cpumask *aff, bool force)
+{
+ struct irq_data *d = irq_desc_get_irq_data(desc);
+
+ if (!irqd_affinity_is_managed(d))
+ return IRQ_STARTUP_NORMAL;
+
+ irqd_clr_managed_shutdown(d);
+
+ if (cpumask_any_and(aff, cpu_online_mask) >= nr_cpu_ids) {
+ /*
+ * Catch code which fiddles with enable_irq() on a managed
+ * and potentially shutdown IRQ. Chained interrupt
+ * installment or irq auto probing should not happen on
+ * managed irqs either.
+ */
+ if (WARN_ON_ONCE(force))
+ return IRQ_STARTUP_ABORT;
+ /*
+ * The interrupt was requested, but there is no online CPU
+ * in it's affinity mask. Put it into managed shutdown
+ * state and let the cpu hotplug mechanism start it up once
+ * a CPU in the mask becomes available.
+ */
+ return IRQ_STARTUP_ABORT;
+ }
+ /*
+ * Managed interrupts have reserved resources, so this should not
+ * happen.
+ */
+ if (WARN_ON(irq_domain_activate_irq(d, false)))
+ return IRQ_STARTUP_ABORT;
+ return IRQ_STARTUP_MANAGED;
+}
+#else
+static __always_inline int
+__irq_startup_managed(struct irq_desc *desc, struct cpumask *aff, bool force)
+{
+ return IRQ_STARTUP_NORMAL;
+}
+#endif
+
+static int __irq_startup(struct irq_desc *desc)
+{
+ struct irq_data *d = irq_desc_get_irq_data(desc);
+ int ret = 0;
+
+ /* Warn if this interrupt is not activated but try nevertheless */
+ WARN_ON_ONCE(!irqd_is_activated(d));
+
+ if (d->chip->irq_startup) {
+ ret = d->chip->irq_startup(d);
+ irq_state_clr_disabled(desc);
+ irq_state_clr_masked(desc);
+ } else {
+ irq_enable(desc);
+ }
+ irq_state_set_started(desc);
+ return ret;
+}
+
+int irq_startup(struct irq_desc *desc, bool resend, bool force)
+{
+ struct irq_data *d = irq_desc_get_irq_data(desc);
+ struct cpumask *aff = irq_data_get_affinity_mask(d);
+ int ret = 0;
+
+ desc->depth = 0;
+
+ if (irqd_is_started(d)) {
+ irq_enable(desc);
+ } else {
+ switch (__irq_startup_managed(desc, aff, force)) {
+ case IRQ_STARTUP_NORMAL:
+ ret = __irq_startup(desc);
+ irq_setup_affinity(desc);
+ break;
+ case IRQ_STARTUP_MANAGED:
+ irq_do_set_affinity(d, aff, false);
+ ret = __irq_startup(desc);
+ break;
+ case IRQ_STARTUP_ABORT:
+ irqd_set_managed_shutdown(d);
+ return 0;
+ }
+ }
+ if (resend)
+ check_irq_resend(desc);
+
+ return ret;
+}
+
+int irq_activate(struct irq_desc *desc)
+{
+ struct irq_data *d = irq_desc_get_irq_data(desc);
+
+ if (!irqd_affinity_is_managed(d))
+ return irq_domain_activate_irq(d, false);
+ return 0;
+}
+
+int irq_activate_and_startup(struct irq_desc *desc, bool resend)
+{
+ if (WARN_ON(irq_activate(desc)))
+ return 0;
+ return irq_startup(desc, resend, IRQ_START_FORCE);
+}
+
+static void __irq_disable(struct irq_desc *desc, bool mask);
+
+void irq_shutdown(struct irq_desc *desc)
+{
+ if (irqd_is_started(&desc->irq_data)) {
+ desc->depth = 1;
+ if (desc->irq_data.chip->irq_shutdown) {
+ desc->irq_data.chip->irq_shutdown(&desc->irq_data);
+ irq_state_set_disabled(desc);
+ irq_state_set_masked(desc);
+ } else {
+ __irq_disable(desc, true);
+ }
+ irq_state_clr_started(desc);
+ }
+ /*
+ * This must be called even if the interrupt was never started up,
+ * because the activation can happen before the interrupt is
+ * available for request/startup. It has it's own state tracking so
+ * it's safe to call it unconditionally.
+ */
+ irq_domain_deactivate_irq(&desc->irq_data);
+}
+
+void irq_enable(struct irq_desc *desc)
+{
+ if (!irqd_irq_disabled(&desc->irq_data)) {
+ unmask_irq(desc);
+ } else {
+ irq_state_clr_disabled(desc);
+ if (desc->irq_data.chip->irq_enable) {
+ desc->irq_data.chip->irq_enable(&desc->irq_data);
+ irq_state_clr_masked(desc);
+ } else {
+ unmask_irq(desc);
+ }
+ }
+}
+
+static void __irq_disable(struct irq_desc *desc, bool mask)
+{
+ if (irqd_irq_disabled(&desc->irq_data)) {
+ if (mask)
+ mask_irq(desc);
+ } else {
+ irq_state_set_disabled(desc);
+ if (desc->irq_data.chip->irq_disable) {
+ desc->irq_data.chip->irq_disable(&desc->irq_data);
+ irq_state_set_masked(desc);
+ } else if (mask) {
+ mask_irq(desc);
+ }
+ }
+}
+
+/**
+ * irq_disable - Mark interrupt disabled
+ * @desc: irq descriptor which should be disabled
+ *
+ * If the chip does not implement the irq_disable callback, we
+ * use a lazy disable approach. That means we mark the interrupt
+ * disabled, but leave the hardware unmasked. That's an
+ * optimization because we avoid the hardware access for the
+ * common case where no interrupt happens after we marked it
+ * disabled. If an interrupt happens, then the interrupt flow
+ * handler masks the line at the hardware level and marks it
+ * pending.
+ *
+ * If the interrupt chip does not implement the irq_disable callback,
+ * a driver can disable the lazy approach for a particular irq line by
+ * calling 'irq_set_status_flags(irq, IRQ_DISABLE_UNLAZY)'. This can
+ * be used for devices which cannot disable the interrupt at the
+ * device level under certain circumstances and have to use
+ * disable_irq[_nosync] instead.
+ */
+void irq_disable(struct irq_desc *desc)
+{
+ __irq_disable(desc, irq_settings_disable_unlazy(desc));
+}
+
+void irq_percpu_enable(struct irq_desc *desc, unsigned int cpu)
+{
+ if (desc->irq_data.chip->irq_enable)
+ desc->irq_data.chip->irq_enable(&desc->irq_data);
+ else
+ desc->irq_data.chip->irq_unmask(&desc->irq_data);
+ cpumask_set_cpu(cpu, desc->percpu_enabled);
+}
+
+void irq_percpu_disable(struct irq_desc *desc, unsigned int cpu)
+{
+ if (desc->irq_data.chip->irq_disable)
+ desc->irq_data.chip->irq_disable(&desc->irq_data);
+ else
+ desc->irq_data.chip->irq_mask(&desc->irq_data);
+ cpumask_clear_cpu(cpu, desc->percpu_enabled);
+}
+
+static inline void mask_ack_irq(struct irq_desc *desc)
+{
+ if (desc->irq_data.chip->irq_mask_ack) {
+ desc->irq_data.chip->irq_mask_ack(&desc->irq_data);
+ irq_state_set_masked(desc);
+ } else {
+ mask_irq(desc);
+ if (desc->irq_data.chip->irq_ack)
+ desc->irq_data.chip->irq_ack(&desc->irq_data);
+ }
+}
+
+void mask_irq(struct irq_desc *desc)
+{
+ if (irqd_irq_masked(&desc->irq_data))
+ return;
+
+ if (desc->irq_data.chip->irq_mask) {
+ desc->irq_data.chip->irq_mask(&desc->irq_data);
+ irq_state_set_masked(desc);
+ }
+}
+
+void unmask_irq(struct irq_desc *desc)
+{
+ if (!irqd_irq_masked(&desc->irq_data))
+ return;
+
+ if (desc->irq_data.chip->irq_unmask) {
+ desc->irq_data.chip->irq_unmask(&desc->irq_data);
+ irq_state_clr_masked(desc);
+ }
+}
+
+void unmask_threaded_irq(struct irq_desc *desc)
+{
+ struct irq_chip *chip = desc->irq_data.chip;
+
+ if (chip->flags & IRQCHIP_EOI_THREADED)
+ chip->irq_eoi(&desc->irq_data);
+
+ unmask_irq(desc);
+}
+
+/*
+ * handle_nested_irq - Handle a nested irq from a irq thread
+ * @irq: the interrupt number
+ *
+ * Handle interrupts which are nested into a threaded interrupt
+ * handler. The handler function is called inside the calling
+ * threads context.
+ */
+void handle_nested_irq(unsigned int irq)
+{
+ struct irq_desc *desc = irq_to_desc(irq);
+ struct irqaction *action;
+ irqreturn_t action_ret;
+
+ might_sleep();
+
+ raw_spin_lock_irq(&desc->lock);
+
+ desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
+
+ action = desc->action;
+ if (unlikely(!action || irqd_irq_disabled(&desc->irq_data))) {
+ desc->istate |= IRQS_PENDING;
+ goto out_unlock;
+ }
+
+ kstat_incr_irqs_this_cpu(desc);
+ irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS);
+ raw_spin_unlock_irq(&desc->lock);
+
+ action_ret = IRQ_NONE;
+ for_each_action_of_desc(desc, action)
+ action_ret |= action->thread_fn(action->irq, action->dev_id);
+
+ if (!noirqdebug)
+ note_interrupt(desc, action_ret);
+
+ raw_spin_lock_irq(&desc->lock);
+ irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);
+
+out_unlock:
+ raw_spin_unlock_irq(&desc->lock);
+}
+EXPORT_SYMBOL_GPL(handle_nested_irq);
+
+static bool irq_check_poll(struct irq_desc *desc)
+{
+ if (!(desc->istate & IRQS_POLL_INPROGRESS))
+ return false;
+ return irq_wait_for_poll(desc);
+}
+
+static bool irq_may_run(struct irq_desc *desc)
+{
+ unsigned int mask = IRQD_IRQ_INPROGRESS | IRQD_WAKEUP_ARMED;
+
+ /*
+ * If the interrupt is not in progress and is not an armed
+ * wakeup interrupt, proceed.
+ */
+ if (!irqd_has_set(&desc->irq_data, mask))
+ return true;
+
+ /*
+ * If the interrupt is an armed wakeup source, mark it pending
+ * and suspended, disable it and notify the pm core about the
+ * event.
+ */
+ if (irq_pm_check_wakeup(desc))
+ return false;
+
+ /*
+ * Handle a potential concurrent poll on a different core.
+ */
+ return irq_check_poll(desc);
+}
+
+/**
+ * handle_simple_irq - Simple and software-decoded IRQs.
+ * @desc: the interrupt description structure for this irq
+ *
+ * Simple interrupts are either sent from a demultiplexing interrupt
+ * handler or come from hardware, where no interrupt hardware control
+ * is necessary.
+ *
+ * Note: The caller is expected to handle the ack, clear, mask and
+ * unmask issues if necessary.
+ */
+void handle_simple_irq(struct irq_desc *desc)
+{
+ raw_spin_lock(&desc->lock);
+
+ if (!irq_may_run(desc))
+ goto out_unlock;
+
+ desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
+
+ if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
+ desc->istate |= IRQS_PENDING;
+ goto out_unlock;
+ }
+
+ kstat_incr_irqs_this_cpu(desc);
+ handle_irq_event(desc);
+
+out_unlock:
+ raw_spin_unlock(&desc->lock);
+}
+EXPORT_SYMBOL_GPL(handle_simple_irq);
+
+/**
+ * handle_untracked_irq - Simple and software-decoded IRQs.
+ * @desc: the interrupt description structure for this irq
+ *
+ * Untracked interrupts are sent from a demultiplexing interrupt
+ * handler when the demultiplexer does not know which device it its
+ * multiplexed irq domain generated the interrupt. IRQ's handled
+ * through here are not subjected to stats tracking, randomness, or
+ * spurious interrupt detection.
+ *
+ * Note: Like handle_simple_irq, the caller is expected to handle
+ * the ack, clear, mask and unmask issues if necessary.
+ */
+void handle_untracked_irq(struct irq_desc *desc)
+{
+ unsigned int flags = 0;
+
+ raw_spin_lock(&desc->lock);
+
+ if (!irq_may_run(desc))
+ goto out_unlock;
+
+ desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
+
+ if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
+ desc->istate |= IRQS_PENDING;
+ goto out_unlock;
+ }
+
+ desc->istate &= ~IRQS_PENDING;
+ irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS);
+ raw_spin_unlock(&desc->lock);
+
+ __handle_irq_event_percpu(desc, &flags);
+
+ raw_spin_lock(&desc->lock);
+ irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);
+
+out_unlock:
+ raw_spin_unlock(&desc->lock);
+}
+EXPORT_SYMBOL_GPL(handle_untracked_irq);
+
+/*
+ * Called unconditionally from handle_level_irq() and only for oneshot
+ * interrupts from handle_fasteoi_irq()
+ */
+static void cond_unmask_irq(struct irq_desc *desc)
+{
+ /*
+ * We need to unmask in the following cases:
+ * - Standard level irq (IRQF_ONESHOT is not set)
+ * - Oneshot irq which did not wake the thread (caused by a
+ * spurious interrupt or a primary handler handling it
+ * completely).
+ */
+ if (!irqd_irq_disabled(&desc->irq_data) &&
+ irqd_irq_masked(&desc->irq_data) && !desc->threads_oneshot)
+ unmask_irq(desc);
+}
+
+/**
+ * handle_level_irq - Level type irq handler
+ * @desc: the interrupt description structure for this irq
+ *
+ * Level type interrupts are active as long as the hardware line has
+ * the active level. This may require to mask the interrupt and unmask
+ * it after the associated handler has acknowledged the device, so the
+ * interrupt line is back to inactive.
+ */
+void handle_level_irq(struct irq_desc *desc)
+{
+ raw_spin_lock(&desc->lock);
+ mask_ack_irq(desc);
+
+ if (!irq_may_run(desc))
+ goto out_unlock;
+
+ desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
+
+ /*
+ * If its disabled or no action available
+ * keep it masked and get out of here
+ */
+ if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
+ desc->istate |= IRQS_PENDING;
+ goto out_unlock;
+ }
+
+ kstat_incr_irqs_this_cpu(desc);
+ handle_irq_event(desc);
+
+ cond_unmask_irq(desc);
+
+out_unlock:
+ raw_spin_unlock(&desc->lock);
+}
+EXPORT_SYMBOL_GPL(handle_level_irq);
+
+#ifdef CONFIG_IRQ_PREFLOW_FASTEOI
+static inline void preflow_handler(struct irq_desc *desc)
+{
+ if (desc->preflow_handler)
+ desc->preflow_handler(&desc->irq_data);
+}
+#else
+static inline void preflow_handler(struct irq_desc *desc) { }
+#endif
+
+static void cond_unmask_eoi_irq(struct irq_desc *desc, struct irq_chip *chip)
+{
+ if (!(desc->istate & IRQS_ONESHOT)) {
+ chip->irq_eoi(&desc->irq_data);
+ return;
+ }
+ /*
+ * We need to unmask in the following cases:
+ * - Oneshot irq which did not wake the thread (caused by a
+ * spurious interrupt or a primary handler handling it
+ * completely).
+ */
+ if (!irqd_irq_disabled(&desc->irq_data) &&
+ irqd_irq_masked(&desc->irq_data) && !desc->threads_oneshot) {
+ chip->irq_eoi(&desc->irq_data);
+ unmask_irq(desc);
+ } else if (!(chip->flags & IRQCHIP_EOI_THREADED)) {
+ chip->irq_eoi(&desc->irq_data);
+ }
+}
+
+/**
+ * handle_fasteoi_irq - irq handler for transparent controllers
+ * @desc: the interrupt description structure for this irq
+ *
+ * Only a single callback will be issued to the chip: an ->eoi()
+ * call when the interrupt has been serviced. This enables support
+ * for modern forms of interrupt handlers, which handle the flow
+ * details in hardware, transparently.
+ */
+void handle_fasteoi_irq(struct irq_desc *desc)
+{
+ struct irq_chip *chip = desc->irq_data.chip;
+
+ raw_spin_lock(&desc->lock);
+
+ if (!irq_may_run(desc))
+ goto out;
+
+ desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
+
+ /*
+ * If its disabled or no action available
+ * then mask it and get out of here:
+ */
+ if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
+ desc->istate |= IRQS_PENDING;
+ mask_irq(desc);
+ goto out;
+ }
+
+ kstat_incr_irqs_this_cpu(desc);
+ if (desc->istate & IRQS_ONESHOT)
+ mask_irq(desc);
+
+ preflow_handler(desc);
+ handle_irq_event(desc);
+
+ cond_unmask_eoi_irq(desc, chip);
+
+ raw_spin_unlock(&desc->lock);
+ return;
+out:
+ if (!(chip->flags & IRQCHIP_EOI_IF_HANDLED))
+ chip->irq_eoi(&desc->irq_data);
+ raw_spin_unlock(&desc->lock);
+}
+EXPORT_SYMBOL_GPL(handle_fasteoi_irq);
+
+/**
+ * handle_edge_irq - edge type IRQ handler
+ * @desc: the interrupt description structure for this irq
+ *
+ * Interrupt occures on the falling and/or rising edge of a hardware
+ * signal. The occurrence is latched into the irq controller hardware
+ * and must be acked in order to be reenabled. After the ack another
+ * interrupt can happen on the same source even before the first one
+ * is handled by the associated event handler. If this happens it
+ * might be necessary to disable (mask) the interrupt depending on the
+ * controller hardware. This requires to reenable the interrupt inside
+ * of the loop which handles the interrupts which have arrived while
+ * the handler was running. If all pending interrupts are handled, the
+ * loop is left.
+ */
+void handle_edge_irq(struct irq_desc *desc)
+{
+ raw_spin_lock(&desc->lock);
+
+ desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
+
+ if (!irq_may_run(desc)) {
+ desc->istate |= IRQS_PENDING;
+ mask_ack_irq(desc);
+ goto out_unlock;
+ }
+
+ /*
+ * If its disabled or no action available then mask it and get
+ * out of here.
+ */
+ if (irqd_irq_disabled(&desc->irq_data) || !desc->action) {
+ desc->istate |= IRQS_PENDING;
+ mask_ack_irq(desc);
+ goto out_unlock;
+ }
+
+ kstat_incr_irqs_this_cpu(desc);
+
+ /* Start handling the irq */
+ desc->irq_data.chip->irq_ack(&desc->irq_data);
+
+ do {
+ if (unlikely(!desc->action)) {
+ mask_irq(desc);
+ goto out_unlock;
+ }
+
+ /*
+ * When another irq arrived while we were handling
+ * one, we could have masked the irq.
+ * Renable it, if it was not disabled in meantime.
+ */
+ if (unlikely(desc->istate & IRQS_PENDING)) {
+ if (!irqd_irq_disabled(&desc->irq_data) &&
+ irqd_irq_masked(&desc->irq_data))
+ unmask_irq(desc);
+ }
+
+ handle_irq_event(desc);
+
+ } while ((desc->istate & IRQS_PENDING) &&
+ !irqd_irq_disabled(&desc->irq_data));
+
+out_unlock:
+ raw_spin_unlock(&desc->lock);
+}
+EXPORT_SYMBOL(handle_edge_irq);
+
+#ifdef CONFIG_IRQ_EDGE_EOI_HANDLER
+/**
+ * handle_edge_eoi_irq - edge eoi type IRQ handler
+ * @desc: the interrupt description structure for this irq
+ *
+ * Similar as the above handle_edge_irq, but using eoi and w/o the
+ * mask/unmask logic.
+ */
+void handle_edge_eoi_irq(struct irq_desc *desc)
+{
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+
+ raw_spin_lock(&desc->lock);
+
+ desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
+
+ if (!irq_may_run(desc)) {
+ desc->istate |= IRQS_PENDING;
+ goto out_eoi;
+ }
+
+ /*
+ * If its disabled or no action available then mask it and get
+ * out of here.
+ */
+ if (irqd_irq_disabled(&desc->irq_data) || !desc->action) {
+ desc->istate |= IRQS_PENDING;
+ goto out_eoi;
+ }
+
+ kstat_incr_irqs_this_cpu(desc);
+
+ do {
+ if (unlikely(!desc->action))
+ goto out_eoi;
+
+ handle_irq_event(desc);
+
+ } while ((desc->istate & IRQS_PENDING) &&
+ !irqd_irq_disabled(&desc->irq_data));
+
+out_eoi:
+ chip->irq_eoi(&desc->irq_data);
+ raw_spin_unlock(&desc->lock);
+}
+#endif
+
+/**
+ * handle_percpu_irq - Per CPU local irq handler
+ * @desc: the interrupt description structure for this irq
+ *
+ * Per CPU interrupts on SMP machines without locking requirements
+ */
+void handle_percpu_irq(struct irq_desc *desc)
+{
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+
+ kstat_incr_irqs_this_cpu(desc);
+
+ if (chip->irq_ack)
+ chip->irq_ack(&desc->irq_data);
+
+ handle_irq_event_percpu(desc);
+
+ if (chip->irq_eoi)
+ chip->irq_eoi(&desc->irq_data);
+}
+
+/**
+ * handle_percpu_devid_irq - Per CPU local irq handler with per cpu dev ids
+ * @desc: the interrupt description structure for this irq
+ *
+ * Per CPU interrupts on SMP machines without locking requirements. Same as
+ * handle_percpu_irq() above but with the following extras:
+ *
+ * action->percpu_dev_id is a pointer to percpu variables which
+ * contain the real device id for the cpu on which this handler is
+ * called
+ */
+void handle_percpu_devid_irq(struct irq_desc *desc)
+{
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+ struct irqaction *action = desc->action;
+ unsigned int irq = irq_desc_get_irq(desc);
+ irqreturn_t res;
+
+ kstat_incr_irqs_this_cpu(desc);
+
+ if (chip->irq_ack)
+ chip->irq_ack(&desc->irq_data);
+
+ if (likely(action)) {
+ trace_irq_handler_entry(irq, action);
+ res = action->handler(irq, raw_cpu_ptr(action->percpu_dev_id));
+ trace_irq_handler_exit(irq, action, res);
+ } else {
+ unsigned int cpu = smp_processor_id();
+ bool enabled = cpumask_test_cpu(cpu, desc->percpu_enabled);
+
+ if (enabled)
+ irq_percpu_disable(desc, cpu);
+
+ pr_err_once("Spurious%s percpu IRQ%u on CPU%u\n",
+ enabled ? " and unmasked" : "", irq, cpu);
+ }
+
+ if (chip->irq_eoi)
+ chip->irq_eoi(&desc->irq_data);
+}
+
+static void
+__irq_do_set_handler(struct irq_desc *desc, irq_flow_handler_t handle,
+ int is_chained, const char *name)
+{
+ if (!handle) {
+ handle = handle_bad_irq;
+ } else {
+ struct irq_data *irq_data = &desc->irq_data;
+#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
+ /*
+ * With hierarchical domains we might run into a
+ * situation where the outermost chip is not yet set
+ * up, but the inner chips are there. Instead of
+ * bailing we install the handler, but obviously we
+ * cannot enable/startup the interrupt at this point.
+ */
+ while (irq_data) {
+ if (irq_data->chip != &no_irq_chip)
+ break;
+ /*
+ * Bail out if the outer chip is not set up
+ * and the interrrupt supposed to be started
+ * right away.
+ */
+ if (WARN_ON(is_chained))
+ return;
+ /* Try the parent */
+ irq_data = irq_data->parent_data;
+ }
+#endif
+ if (WARN_ON(!irq_data || irq_data->chip == &no_irq_chip))
+ return;
+ }
+
+ /* Uninstall? */
+ if (handle == handle_bad_irq) {
+ if (desc->irq_data.chip != &no_irq_chip)
+ mask_ack_irq(desc);
+ irq_state_set_disabled(desc);
+ if (is_chained)
+ desc->action = NULL;
+ desc->depth = 1;
+ }
+ desc->handle_irq = handle;
+ desc->name = name;
+
+ if (handle != handle_bad_irq && is_chained) {
+ unsigned int type = irqd_get_trigger_type(&desc->irq_data);
+
+ /*
+ * We're about to start this interrupt immediately,
+ * hence the need to set the trigger configuration.
+ * But the .set_type callback may have overridden the
+ * flow handler, ignoring that we're dealing with a
+ * chained interrupt. Reset it immediately because we
+ * do know better.
+ */
+ if (type != IRQ_TYPE_NONE) {
+ __irq_set_trigger(desc, type);
+ desc->handle_irq = handle;
+ }
+
+ irq_settings_set_noprobe(desc);
+ irq_settings_set_norequest(desc);
+ irq_settings_set_nothread(desc);
+ desc->action = &chained_action;
+ irq_activate_and_startup(desc, IRQ_RESEND);
+ }
+}
+
+void
+__irq_set_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
+ const char *name)
+{
+ unsigned long flags;
+ struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, 0);
+
+ if (!desc)
+ return;
+
+ __irq_do_set_handler(desc, handle, is_chained, name);
+ irq_put_desc_busunlock(desc, flags);
+}
+EXPORT_SYMBOL_GPL(__irq_set_handler);
+
+void
+irq_set_chained_handler_and_data(unsigned int irq, irq_flow_handler_t handle,
+ void *data)
+{
+ unsigned long flags;
+ struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, 0);
+
+ if (!desc)
+ return;
+
+ desc->irq_common_data.handler_data = data;
+ __irq_do_set_handler(desc, handle, 1, NULL);
+
+ irq_put_desc_busunlock(desc, flags);
+}
+EXPORT_SYMBOL_GPL(irq_set_chained_handler_and_data);
+
+void
+irq_set_chip_and_handler_name(unsigned int irq, struct irq_chip *chip,
+ irq_flow_handler_t handle, const char *name)
+{
+ irq_set_chip(irq, chip);
+ __irq_set_handler(irq, handle, 0, name);
+}
+EXPORT_SYMBOL_GPL(irq_set_chip_and_handler_name);
+
+void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set)
+{
+ unsigned long flags, trigger, tmp;
+ struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
+
+ if (!desc)
+ return;
+
+ /*
+ * Warn when a driver sets the no autoenable flag on an already
+ * active interrupt.
+ */
+ WARN_ON_ONCE(!desc->depth && (set & _IRQ_NOAUTOEN));
+
+ irq_settings_clr_and_set(desc, clr, set);
+
+ trigger = irqd_get_trigger_type(&desc->irq_data);
+
+ irqd_clear(&desc->irq_data, IRQD_NO_BALANCING | IRQD_PER_CPU |
+ IRQD_TRIGGER_MASK | IRQD_LEVEL | IRQD_MOVE_PCNTXT);
+ if (irq_settings_has_no_balance_set(desc))
+ irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
+ if (irq_settings_is_per_cpu(desc))
+ irqd_set(&desc->irq_data, IRQD_PER_CPU);
+ if (irq_settings_can_move_pcntxt(desc))
+ irqd_set(&desc->irq_data, IRQD_MOVE_PCNTXT);
+ if (irq_settings_is_level(desc))
+ irqd_set(&desc->irq_data, IRQD_LEVEL);
+
+ tmp = irq_settings_get_trigger_mask(desc);
+ if (tmp != IRQ_TYPE_NONE)
+ trigger = tmp;
+
+ irqd_set(&desc->irq_data, trigger);
+
+ irq_put_desc_unlock(desc, flags);
+}
+EXPORT_SYMBOL_GPL(irq_modify_status);
+
+/**
+ * irq_cpu_online - Invoke all irq_cpu_online functions.
+ *
+ * Iterate through all irqs and invoke the chip.irq_cpu_online()
+ * for each.
+ */
+void irq_cpu_online(void)
+{
+ struct irq_desc *desc;
+ struct irq_chip *chip;
+ unsigned long flags;
+ unsigned int irq;
+
+ for_each_active_irq(irq) {
+ desc = irq_to_desc(irq);
+ if (!desc)
+ continue;
+
+ raw_spin_lock_irqsave(&desc->lock, flags);
+
+ chip = irq_data_get_irq_chip(&desc->irq_data);
+ if (chip && chip->irq_cpu_online &&
+ (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) ||
+ !irqd_irq_disabled(&desc->irq_data)))
+ chip->irq_cpu_online(&desc->irq_data);
+
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
+ }
+}
+
+/**
+ * irq_cpu_offline - Invoke all irq_cpu_offline functions.
+ *
+ * Iterate through all irqs and invoke the chip.irq_cpu_offline()
+ * for each.
+ */
+void irq_cpu_offline(void)
+{
+ struct irq_desc *desc;
+ struct irq_chip *chip;
+ unsigned long flags;
+ unsigned int irq;
+
+ for_each_active_irq(irq) {
+ desc = irq_to_desc(irq);
+ if (!desc)
+ continue;
+
+ raw_spin_lock_irqsave(&desc->lock, flags);
+
+ chip = irq_data_get_irq_chip(&desc->irq_data);
+ if (chip && chip->irq_cpu_offline &&
+ (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) ||
+ !irqd_irq_disabled(&desc->irq_data)))
+ chip->irq_cpu_offline(&desc->irq_data);
+
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
+ }
+}
+
+#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
+
+#ifdef CONFIG_IRQ_FASTEOI_HIERARCHY_HANDLERS
+/**
+ * handle_fasteoi_ack_irq - irq handler for edge hierarchy
+ * stacked on transparent controllers
+ *
+ * @desc: the interrupt description structure for this irq
+ *
+ * Like handle_fasteoi_irq(), but for use with hierarchy where
+ * the irq_chip also needs to have its ->irq_ack() function
+ * called.
+ */
+void handle_fasteoi_ack_irq(struct irq_desc *desc)
+{
+ struct irq_chip *chip = desc->irq_data.chip;
+
+ raw_spin_lock(&desc->lock);
+
+ if (!irq_may_run(desc))
+ goto out;
+
+ desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
+
+ /*
+ * If its disabled or no action available
+ * then mask it and get out of here:
+ */
+ if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
+ desc->istate |= IRQS_PENDING;
+ mask_irq(desc);
+ goto out;
+ }
+
+ kstat_incr_irqs_this_cpu(desc);
+ if (desc->istate & IRQS_ONESHOT)
+ mask_irq(desc);
+
+ /* Start handling the irq */
+ desc->irq_data.chip->irq_ack(&desc->irq_data);
+
+ preflow_handler(desc);
+ handle_irq_event(desc);
+
+ cond_unmask_eoi_irq(desc, chip);
+
+ raw_spin_unlock(&desc->lock);
+ return;
+out:
+ if (!(chip->flags & IRQCHIP_EOI_IF_HANDLED))
+ chip->irq_eoi(&desc->irq_data);
+ raw_spin_unlock(&desc->lock);
+}
+EXPORT_SYMBOL_GPL(handle_fasteoi_ack_irq);
+
+/**
+ * handle_fasteoi_mask_irq - irq handler for level hierarchy
+ * stacked on transparent controllers
+ *
+ * @desc: the interrupt description structure for this irq
+ *
+ * Like handle_fasteoi_irq(), but for use with hierarchy where
+ * the irq_chip also needs to have its ->irq_mask_ack() function
+ * called.
+ */
+void handle_fasteoi_mask_irq(struct irq_desc *desc)
+{
+ struct irq_chip *chip = desc->irq_data.chip;
+
+ raw_spin_lock(&desc->lock);
+ mask_ack_irq(desc);
+
+ if (!irq_may_run(desc))
+ goto out;
+
+ desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
+
+ /*
+ * If its disabled or no action available
+ * then mask it and get out of here:
+ */
+ if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
+ desc->istate |= IRQS_PENDING;
+ mask_irq(desc);
+ goto out;
+ }
+
+ kstat_incr_irqs_this_cpu(desc);
+ if (desc->istate & IRQS_ONESHOT)
+ mask_irq(desc);
+
+ preflow_handler(desc);
+ handle_irq_event(desc);
+
+ cond_unmask_eoi_irq(desc, chip);
+
+ raw_spin_unlock(&desc->lock);
+ return;
+out:
+ if (!(chip->flags & IRQCHIP_EOI_IF_HANDLED))
+ chip->irq_eoi(&desc->irq_data);
+ raw_spin_unlock(&desc->lock);
+}
+EXPORT_SYMBOL_GPL(handle_fasteoi_mask_irq);
+
+#endif /* CONFIG_IRQ_FASTEOI_HIERARCHY_HANDLERS */
+
+/**
+ * irq_chip_enable_parent - Enable the parent interrupt (defaults to unmask if
+ * NULL)
+ * @data: Pointer to interrupt specific data
+ */
+void irq_chip_enable_parent(struct irq_data *data)
+{
+ data = data->parent_data;
+ if (data->chip->irq_enable)
+ data->chip->irq_enable(data);
+ else
+ data->chip->irq_unmask(data);
+}
+EXPORT_SYMBOL_GPL(irq_chip_enable_parent);
+
+/**
+ * irq_chip_disable_parent - Disable the parent interrupt (defaults to mask if
+ * NULL)
+ * @data: Pointer to interrupt specific data
+ */
+void irq_chip_disable_parent(struct irq_data *data)
+{
+ data = data->parent_data;
+ if (data->chip->irq_disable)
+ data->chip->irq_disable(data);
+ else
+ data->chip->irq_mask(data);
+}
+EXPORT_SYMBOL_GPL(irq_chip_disable_parent);
+
+/**
+ * irq_chip_ack_parent - Acknowledge the parent interrupt
+ * @data: Pointer to interrupt specific data
+ */
+void irq_chip_ack_parent(struct irq_data *data)
+{
+ data = data->parent_data;
+ data->chip->irq_ack(data);
+}
+EXPORT_SYMBOL_GPL(irq_chip_ack_parent);
+
+/**
+ * irq_chip_mask_parent - Mask the parent interrupt
+ * @data: Pointer to interrupt specific data
+ */
+void irq_chip_mask_parent(struct irq_data *data)
+{
+ data = data->parent_data;
+ data->chip->irq_mask(data);
+}
+EXPORT_SYMBOL_GPL(irq_chip_mask_parent);
+
+/**
+ * irq_chip_unmask_parent - Unmask the parent interrupt
+ * @data: Pointer to interrupt specific data
+ */
+void irq_chip_unmask_parent(struct irq_data *data)
+{
+ data = data->parent_data;
+ data->chip->irq_unmask(data);
+}
+EXPORT_SYMBOL_GPL(irq_chip_unmask_parent);
+
+/**
+ * irq_chip_eoi_parent - Invoke EOI on the parent interrupt
+ * @data: Pointer to interrupt specific data
+ */
+void irq_chip_eoi_parent(struct irq_data *data)
+{
+ data = data->parent_data;
+ data->chip->irq_eoi(data);
+}
+EXPORT_SYMBOL_GPL(irq_chip_eoi_parent);
+
+/**
+ * irq_chip_set_affinity_parent - Set affinity on the parent interrupt
+ * @data: Pointer to interrupt specific data
+ * @dest: The affinity mask to set
+ * @force: Flag to enforce setting (disable online checks)
+ *
+ * Conditinal, as the underlying parent chip might not implement it.
+ */
+int irq_chip_set_affinity_parent(struct irq_data *data,
+ const struct cpumask *dest, bool force)
+{
+ data = data->parent_data;
+ if (data->chip->irq_set_affinity)
+ return data->chip->irq_set_affinity(data, dest, force);
+
+ return -ENOSYS;
+}
+EXPORT_SYMBOL_GPL(irq_chip_set_affinity_parent);
+
+/**
+ * irq_chip_set_type_parent - Set IRQ type on the parent interrupt
+ * @data: Pointer to interrupt specific data
+ * @type: IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h
+ *
+ * Conditional, as the underlying parent chip might not implement it.
+ */
+int irq_chip_set_type_parent(struct irq_data *data, unsigned int type)
+{
+ data = data->parent_data;
+
+ if (data->chip->irq_set_type)
+ return data->chip->irq_set_type(data, type);
+
+ return -ENOSYS;
+}
+EXPORT_SYMBOL_GPL(irq_chip_set_type_parent);
+
+/**
+ * irq_chip_retrigger_hierarchy - Retrigger an interrupt in hardware
+ * @data: Pointer to interrupt specific data
+ *
+ * Iterate through the domain hierarchy of the interrupt and check
+ * whether a hw retrigger function exists. If yes, invoke it.
+ */
+int irq_chip_retrigger_hierarchy(struct irq_data *data)
+{
+ for (data = data->parent_data; data; data = data->parent_data)
+ if (data->chip && data->chip->irq_retrigger)
+ return data->chip->irq_retrigger(data);
+
+ return 0;
+}
+
+/**
+ * irq_chip_set_vcpu_affinity_parent - Set vcpu affinity on the parent interrupt
+ * @data: Pointer to interrupt specific data
+ * @vcpu_info: The vcpu affinity information
+ */
+int irq_chip_set_vcpu_affinity_parent(struct irq_data *data, void *vcpu_info)
+{
+ data = data->parent_data;
+ if (data->chip->irq_set_vcpu_affinity)
+ return data->chip->irq_set_vcpu_affinity(data, vcpu_info);
+
+ return -ENOSYS;
+}
+
+/**
+ * irq_chip_set_wake_parent - Set/reset wake-up on the parent interrupt
+ * @data: Pointer to interrupt specific data
+ * @on: Whether to set or reset the wake-up capability of this irq
+ *
+ * Conditional, as the underlying parent chip might not implement it.
+ */
+int irq_chip_set_wake_parent(struct irq_data *data, unsigned int on)
+{
+ data = data->parent_data;
+ if (data->chip->irq_set_wake)
+ return data->chip->irq_set_wake(data, on);
+
+ return -ENOSYS;
+}
+#endif
+
+/**
+ * irq_chip_compose_msi_msg - Componse msi message for a irq chip
+ * @data: Pointer to interrupt specific data
+ * @msg: Pointer to the MSI message
+ *
+ * For hierarchical domains we find the first chip in the hierarchy
+ * which implements the irq_compose_msi_msg callback. For non
+ * hierarchical we use the top level chip.
+ */
+int irq_chip_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
+{
+ struct irq_data *pos = NULL;
+
+#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
+ for (; data; data = data->parent_data)
+#endif
+ if (data->chip && data->chip->irq_compose_msi_msg)
+ pos = data;
+ if (!pos)
+ return -ENOSYS;
+
+ pos->chip->irq_compose_msi_msg(pos, msg);
+
+ return 0;
+}
+
+/**
+ * irq_chip_pm_get - Enable power for an IRQ chip
+ * @data: Pointer to interrupt specific data
+ *
+ * Enable the power to the IRQ chip referenced by the interrupt data
+ * structure.
+ */
+int irq_chip_pm_get(struct irq_data *data)
+{
+ int retval;
+
+ if (IS_ENABLED(CONFIG_PM) && data->chip->parent_device) {
+ retval = pm_runtime_get_sync(data->chip->parent_device);
+ if (retval < 0) {
+ pm_runtime_put_noidle(data->chip->parent_device);
+ return retval;
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * irq_chip_pm_put - Disable power for an IRQ chip
+ * @data: Pointer to interrupt specific data
+ *
+ * Disable the power to the IRQ chip referenced by the interrupt data
+ * structure, belongs. Note that power will only be disabled, once this
+ * function has been called for all IRQs that have called irq_chip_pm_get().
+ */
+int irq_chip_pm_put(struct irq_data *data)
+{
+ int retval = 0;
+
+ if (IS_ENABLED(CONFIG_PM) && data->chip->parent_device)
+ retval = pm_runtime_put(data->chip->parent_device);
+
+ return (retval < 0) ? retval : 0;
+}